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Insulator Transition (insulator + transition)

Distribution by Scientific Domains

Physics and Astronomy	40%

Selected Abstracts

Metal,Insulator Transition and Large Thermoelectric Power of a Layered Palladium Oxide: PbPdO2.

CHEMINFORM, Issue 17 2005
T. C. Ozawa
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

ChemInform Abstract: Ferrimagnetism and Metal,Insulator Transitions in the LaMnxRu1-xO3 Perovskites.

CHEMINFORM, Issue 37 2002
Z. Serpil Goenen
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Field-Structured Chemiresistors: Field-Structured Chemiresistors (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 10 2010
Mater.
D. H. Read and J. E. Martin report on page 1577 the use of field-structured composites as improved chemiresistors. Magnetic fields are used to organize Au-coated magnetic particles into electrically conducting pathways within a polymer matrix. Though many structures are possible, a biaxial field leads to stacked particle sheets, as illustrated on the cover. These sensors undergo a reversible conductor,insulator transition over such a narrow concentration range that they behave like chemical switches. This switching point is tuned by controlling polymer stresses. [source]

Effects of correlated disorder on the magneto-transport in colossal magnetoresistance manganites

PHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 4 2009
M. Egilmez
Abstract Monte-Carlo simulations predict that a local correlated disorder is responsible for many of the novel transport and magnetic properties of colossal magnetoresistance (CMR) materials such as manganites. One important prediction of these models is that the resistivity at the metal,insulator transition (MIT) in manganites depends strongly on the correlated quenched disorder. However, experimental confirmation has been challenging since it is difficult to control the amount of disorder in these compounds. We carried out experiments on Sm0.55Sr0.45MnO3, a prototypical CMR manganite with a sharp MIT, whereby the oxygen-related disorder is systematically enhanced by low temperature thermal activation. We observe dramatic changes in the temperature dependence of resistivity at the MIT as the amount of quenched disorder is increased, occurring in a manner that is in agreement with theoretical predictions. Temperature dependence of resistivity of Sm0.55Sr0.45MnO3 for different annealing times at 350 °C in vacuum. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Optical properties of correlated materials , Or why intelligent windows may look dirty,

PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 9 2009
Jan M. Tomczak
Abstract Materials with strong electronic Coulomb correlations play an increasing role in modern materials applications. "Thermochromic" systems, which exhibit thermally induced changes in their optical response, provide a particularly interesting case. The optical switching associated with the metal,insulator transition of vanadium dioxide (VO2), for example, has been proposed for use in numerous applications, ranging from anti-laser shields to "intelligent" windows, which selectively filter radiative heat in hot weather conditions. Are present-day electronic structure techniques able to describe, or , eventually even predict , such a kind of behavior? How far are we from materials design using correlated oxides? These are the central questions we try to address in this article. We review recent attempts of calculating optical properties of correlated materials within dynamical mean field theory, and summarize results for VO2 obtained within a novel scheme aiming at particularly simple and efficient calculations of optical transition matrix elements within localized basis sets. Finally, by optimizing the geometry of "intelligent windows," we argue that this kind of technique can, in principle, be used to provide guidance for experiments, thus giving a rather optimistic answer to the above questions. [source]